Muffler and filter



March 24, C. A BROCK ET AL MUFFLER AND FILTER Filed April l, 1948 Patented Mar. 24, l1953 MUFFLER AND FILTER Clarence A. Brock and Thomas Richard Hunter,

Toledo, Ohio, assignors to Martin Parry Corporation, Toledo, Ohio, a corporation of Delaware Application April 1, 1948, Serial No. 18,348

1 This invention relates to cleaning or filtering means generally and more particularly vto a readily replaceable filter means adapted for removing dirt rand dust from fluids such as air, for example, contaminated therewith.

Air filtering means of this general character, hereto-fore utilized, while being readily replaceable, V.possessed the one great disadvantage that after use, no matter how much care was exercised in removing the used lter f-or replacement pu-rposes, some or a good deal of the dirt precipitant adhering to the sides of th-e lter would become dislodged and fall into the working part or parts of a device such as a suction clean-er, for example, with which it had been operatively assembled. By virtue of the .present invention novel filter means have been provided with the use of which any'dirt precipiltant which becomes dislodged from the filter during replacement, or at any other time, falls into a receptacle or trap formed as a part of the iilter so that the foregoing disadvantage surrounding known filter-elements has been overcome.

' An object of the present invention therefore is to provide a novel and improved filter expedient for contaminated iluids such as air, for example. Another object of the invention is to provide anovel and replaceable vfilter for iiuids having means formed `'as a part thereof which will interycept any dint precipitant normally clinging to the filter which may become dislodged therefrom duringfremo'val ofthe filter for replacement purposes or at any other time.

-Apf'urther object is to provid-e a novel air filterA of the character described adapt-ed to function in the desired manner Whether air flowing therethrough be from the inside of the filter tothe outside thereof, or Whether such air flo-w is reversed, namely, from the outside of the iilter to the inside thereof.

' Another'object is to provide a novel air filter having a maximum filtering or cleaning surface area arranged in a minimum amount of space, the cleaning element thereof being provided Kas a hollow annulus having a predetermined width andformed with a series of accordion pleats or folds`,.the peripheries of the folds being alternately arranged atthe outside and inside diameter o-f the annulus.

The above and further objects and advantages of the invention will appear more fully hereinafter from a consideration of the detail-ed dements of the invention are iiiusirated. n is 'to 3 Claims. (Cl. 18S-71) 2 be expressly understood, however, that the dra ing is for the purpose of illustration only and is not to be construed as dening the limits of the invention.

In the drawings wherein like reference char-- acters refer to like parts throughout the dinerent views: t

Figure 1 is 'a side elevation vi-ew in section of.

one embodiment of the novel fluid filter of the present invention illustrating a useful applica-- tion thereof;

Figure 2 is a fragmentary sectional view of the filter taken substantially along line 2 2 of Figure. l; and

Figure 3 is a side elevation view in section of' a second embodiment of the novel uid lter hereof. f

Referring now to the drawings for a more detailed description of the present invention and more particularly to Figure 1 thereof, the novel fluid or air filter hereof, generally designated with.

I3 which is provided at its inner end With a series of apertures I4 permitting communication ofthe interior of body portion II with the exterior of the cleaner through an outlet I5 formed in an ex#A ternal cover I-6 having a lifting bail I'I suitably fastened thereto.

While a liquid cham-ber is interposed betweenthe cleaning nozzle and the motor or pump cham-v ber to clean .the incoming air from Ithe dirt and dust contained therein which enters the nozzle some of the dirt may pass with the air through the outlet I5. VSince it is undesirable that such contaminated air be discharged from outlet I5V to the room or enclosure being cleaned, the novel air lter hereof is provided between the cleaner and its outlet to assure nothing but clean air from passing out of the outlet.

The novel air lter I0 of the presen-t invention compris-es two spaced annular plates IIB and I9, the upper plate I8 being soli-d and formed of some strong and substantially non-porous, inaterial, such as cardboard or a series of laminated sheets of paper bon-ded to Veach other by way of.

a suitable adhesive, and the lower plate I9 being" formed of the same material but having a central opening 20 therein by virtue of which the filter element may be nested with cup I3 and may rest by way of its low-er plate I9 on the upper surface of cover I2. By virtue of this arrangement ai-r flowing from body portion II, as designated by the arrows in Figure 1, must pass through filter I by way ofapertures :I4'formed in cup I3 before it can pass'to outlet I5.

interposed between the outer portion of plates I-8 and I9, is a lter element 2I formed of suitable filtering paper which is porous enough to permit clean air to flow therethrough but which, however, is fine enough to prevent passage. therethrough of .dust and dirt particles suspended'in the contaminated air which it is desired to clean. Filter element 2I comprises a sheet of filter paper which is formed with a series of folds in the manner of accordion folds and thereafter formed into a hollow cylinder having a wall of a predetermined thickness, the outer periphery of which isf; determined bythe locus: of .the peak-s of theY out-er folds .22 tFigu-rez) and the inner periph-ery of which is determined by the Ipeaks -of 'the alternate. inner folds 23. The inner surfaces of the platesv I8 .and I9 are .provided with a suitable adhesive .24 whereby filter element 2| may -be assembled between. and secured to both plates.

Theinnerperiphery of lower plate I9 is made to` .extend inwardly beyond the inner periphery of filter element 2 I, which is defined by the peaks ofnitsf innerfolds. 23, and its innermost end is dishe'd" upwardly asat 25 so as to conform to the conguration of the surface on which it will normally rest, such surfaces .in the example shown in Figure 1,.beingr the top portion of cover I2 where it joins the side walls of cup I3. Interposed between the dishedV portion 25 of lower plate I'S'Vand the. peaks of the inner folds 23 of filter element'2l, and in spaced relation with the latter, isa vsubstantially rigid cone 26 formed of suitable material` such as the stiff paper utilized for the upper and lower plates. The bottom of cone 26;. is suitably secured to the upper portion of plate I9' by.' way-of adhesive material 21. By the provision; ofthe cone 26, a novel trap or chamberis defined by reason of which any dust or dirt which has been deposited on the inner wall of. the; filter element 2| during a filtering operation-and` which may have been dislodged therefrom upon removalofthe lter for replacement purposes, will. fall intosuch chamber and will bei-retained thereinthereby preventing the dirt from inadvertently falling through apertures I4, for example,.back. into body portion II.

It will now-be readily apparent that by providing the novel lter I0 hereof between the outlet oft a'. device` such as. al suction cleaner andL the inlet.` thereof, as shown in Figure l, dust and. dirt laderr air will.. pass through apertures I4 oficup I3; and will .impinge tangentially on the various innersurfacesof. the walls defined. by filter. element 'ZI-,.in. such a manner. that the foreign matterin the .airv will. cling to or be deposited on thewallsfofthe filtering element permitting clean air only lto pass through the. walls to outlet l5. nthe eventtha-t seine of the dirt particles are dislodged from the walls, they will fall into and collect within the' trap or chamber defined by the inner;periphery of ltering'element 2|'v at the ir'inersurface of'cone 26 so' that the undesirable foreign matter rwill at alltimes be within theltersandfuponremoval of the filter for replacement purposes the dirt will be lo'calized'and' 4 will be therefore readily disposable with the used filter.

While lter I0 has been described in connection with its ltering and cleaning properties only, it will be apparent that by providing the filter above the motor and pump, normally mounted within body portion II, it will also act as a muier to minimize the amount of noise generated by the working-parts of the cleaner. In order that filter I0 may be strengthened where necessary, a reinforcing rib or annular disk 28 may be secured to the. top of upper plate I8 as shown in Figure 1.

The novel filter of the present invention has been illustratedin, Figure 1 in one of its many applications. wherecontaminated air passes into the interior of theV lter permitting passage of cleanV air from. the outside thereof. However, the novel filter ofthe present invention is equally adaptedv for reverse flow of the air to be cleaned, namely, the contaminated air may flow from the outside of the filter to pass clean air. to vthe interior thereof. The latter application for reverse air ow is clearly shown in Figure 3 of the draw-V ing wherein a lter element 50, similar in all respects to filtering element-2l of Figure 1, is suitably fastened between upper and lower plates 5I and 52. The outer ends of the plates extend considerably beyond the outer periphery of filtering element 50 and have interposed therebetween an annularwall 53, the inner portion of which together with the outer periphery of filtering element 50, denes a trap or chamber for collecting any and all dirt particles which during a filtering operation have been deposited on the outside walls of iiltering element 50 and have subsequently become dislodged therefroml In this lastapplication, a cover plate 54 may be formed with a central cup shaped portion 55 having apertures 56 therein, the filter resting by virtue of the inner ends of its lower plate which is apertured for this purpose about cup 55. Upper plate 5I is provided at its outer periphery with a series of apertures 5'! which communicate the interior ofv the chamber dened by the outer wall of filtering. element 55 and the inner portionof wall 53 with the exterior of the lter.

Contaminated air in this instance flows, as shown by the arrows in Figure 3, from the out side of the filter through apertures. 51 to the outer. wall of filter element 50 t0 impinge tangentially on the various walls of the. filtering element, the iilteringelement being impervious to dirt and dust, obstructing passage of the latter sothat it collects and is deposited upon the outsidev of the walls of the filtering element and clean air alone. passes through the walls to the interior of the filter and out. therefrom. through apertures 56. It will be readily apparent that if the foreign matter deposited on the outside of the ltering element 50 falls or becomes dislodged therefrom, it will fall and be. collectedwithin the. chamber defined by the inner periphery of wall 53 and the' outer periphery of ltering element 50. Thus the dirt and the filter may be readily. removed together for replacement purposes,

A. stifl'ening plate or rib (not shown) may be secured to the upper part of plate 5I for reinforcing or stiifening the filter in the same manner that plate 28 of Figure 1 is utilized.

It will now be readily apparent to those skilled in the art that anew and novel filter has been provided by thev present invention wherein any dirt or dust whichv has been dislodged from the wallsof the filtering element. will. not fall into the device. with which the lteris` assembled.

but will instead fall into a suitable receptacle formed as a part of the ltering element.

Although the lter has been described in its application to a suction cleaner it is to be specically understood that it is not limited to such use but may be used wherever it is desired to segregate foreign matter contained in any working uid such as air, for example.

Although but two embodiments of the invention have been illustrated and described, various changes and modiiications in the form and relative arrangement of the parts, which will now appear to those skilled in the art, may be made without departing from the spirit and scope of the invention. For example, instead of providing the aperture 20 in lower plate I9 alone, a second aperture in alignment with the rst aperture may be provided in top plate I8 whereby the lter may be sleeved about a motor or pump housing having side perforations through which air may be exhausted directly into the interior of the lter.

What is claimed is:

1. A gas filter comprising an annular iilter of plaited lter paper and having a vertical axis, the inner periphery of said ilter comprising an inlet and the outer periphery of said lter comprising an outlet whereby gas flows radially from the inside to the outside of the filter, axially and vertically spaced cardboard plates glued to opposite ends of said lter and disposed radially and horizontally With respect to said vertical axis, the lower of said plates having a central inlet opening for admitting gas to said inner periphery but of substantially less diameter than said inner periphery, and an annular cardboard wall with a vertical axis and of substantially less diameter than said inner periphery and substantially less length than said lter glued at its lower end to said lower plate around said opening to form with said lower plate a trap for solid particles separated from the gas at said inlet periphery.

2. The invention as set forth in claim 1 wherein said annular wall is truste-conical and its end of larger diameter is glued to said lower plate intermediate said opening and inner periphery and its other end of smaller diameter has a diameter which is substantially the same as said opening whereby the edges of said opening and smaller end are adapted to receive a cylindrical inlet conduit having a vertical axis.

3. The invention as set forth in claim 2 wherein an annular portion of said lower plate immediately surrounding said opening is formed on an angle with respect to the rest of the plate and extends axially toward the other plate.

CLARENCE A. BROCK. THOMAS RICHARD HUNTER.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS 

